Daily kWh generation question

Toodles_27 · 03-05-2025 12:55PM #1

Had solar panels installed yesterday. While I did due diligence on installer etc, I still unsure as to how much exactly it is going to affect our electricity bills - which was only reason for installing.

Have 20 panels, inverter, battery and water heating system. Sell back excess to grid. Have the apps.

My question is, how much energy generation is considered “good”?
For example, yesterday system was turned on at roughly 1pm and it generated 41.1kWh of energy for all of yesterday. Is this a “good” figure?

While acknowledging that every house use can be vastly different, what figure should I be aiming for in daily generation? Today we are up to 19.8kWh at 12.55pm

StormForce13 · 03-05-2025 01:27PM

For starters, in what direction is/are your panels facing?

What size is your system? (20*~0.4 kW panels suggest that it should be a 8kW system)

(My 4.1 kW West facing system gave me 25.3 kWh yesterday. That was my best return of 2025.)

idc · 03-05-2025 01:43PM

I'd say 41kWh excellent and that was only from 1pm! I only generated 26kWh yesterday. As @StormForce13 asked orientation will have an impact, as will size of array. Number of panels is less relevant as panels come in different sizes. Better to report kWp of your system.
I have only 6kWp SE/SW but a pure South facing system will generate more in good weather.

terrarev · 03-05-2025 02:01PM

Also bare in mind you'll have a 5kw inverter so no matter how much your panels could produce in theory you can only convert 5kw of that for household use. You can go above that 5kw if you have space in your batteries to store electricity but that probably isn't going to have a massive impact unless you have a lot of capacity and don't charge from the grid at night.